Blade servers have been widely used in various applications. A rack server system includes blade servers in a rack system for convenience of operation.
A blade server of the rack server system functions as a computer with complete functions. In other words, a blade server has peripheral devices such as a power supplier and a heat dissipation device in addition to its core components (such as CPU, motherboard, random access memory (RAM) and hard disc).
If AC-grid power is unstable, operations of the server will be unstable (such as shut-down) and data stored in the server may even be damaged. An uninterruptible power system (UPS) is used to avoid data loss and damage to electronic apparatus if power supply is abnormal, so as to effectively protect internal elements of the server and assure lifespan and accuracy of the server. However, reliability of existing UPS is still not satisfactory.
So, a battery backup unit (BBU) is in the rack server system to replace/assist the UPS for low cost, high efficiency and high stability.
However, during the battery module of the BBU is broken or unloaded for maintenance or service, the operation stability of the rack server system will be affected due to insufficient power supplied by the BBU if the AC-grid power happens to be unstable/abnormal/interrupted.
Besides, to maintain the normal operation of the BBU, a battery self-discharging test is performed every period of time so as to judge whether the battery of the BBU is normal according to a discharging curve thereof. During the battery self-discharging test, the operation stability of the rack server system will be affected due to insufficient power supplied from the BBU if the AC-grid power happens to be unstable/abnormal/interrupted.
In addition, among the current practices, during the BBU is maintained, the rack server system is usually turned off, which is inconvenient to user and/or administrator.